The Emerald Lake Basin forms a subalpine watershed in the upper drainage of the Marble Fork of the Kaweah River in Sequoia National Park. The basin is 120 ha in area and covers an elevational range from 2804 m at Emerald Lake to 3416 m at the summit of Alta Peak. The flora of the basin includes 202 vascular plant species, distributed into 132 genera and 41 families, with the Asteraceae (25 species) and Poaceae (23 species) as the largest families. Herbaceous perennials make up about three-fourths of the flora, but unlike alpine habitats many of these are relatively tall upright species, particularly in wet habitats. The woody plant flora includes five tree species, all conifers, with Pinus monticola as the dominant. There are 19 species of woody shrubs present, including six evergreen and 13 winter deciduous species. Eight plant habitat types were delineated on the basis of geomorphic position related to soil conditions and water availability that influence species composition (Billings 1974). These were subalpine conifer forest, willow thicket, wet meadows, moist rock crevices, dry meadows, dry rock crevices, colluvium, and fellfields.